Pencil sharpener



Jan. 27, 1953 R. "c. G WIN, JR

PENCIL SHARPENER Filed June 1, 1951 INVENTOR. Robert C 6mm Jr" W ATTORNEY Patented Jan. 27, 1953 UNITED STATES PATENT OFFICE,

PENCIL SHARPENER,

Robert C. G win, Jr., Barrington, R. I. I Application June 1, 1951, Serial No. 229,357

- Claims.. l The present invention pertains to a pencil sharpener and more particularly to a pencil sharpener adapted for quick one hand operation.

One object of the present invention is to provide a pencil sharpener capable of being actuated by one hand.

Another object of the present invention is to provide a pencil sharpener adapted to be actuated by pressing the pencil to be sharpened thereinto.

Another object of the present invention is to provide a pencil sharpener adapted to be actuated by a reciprocating motion of the pencil to be sharpened.

Another object of the present invention is to provide a pencil sharpener having a cutting blade therein which is rotated continuously by a reciprocating motion of the pencil being sharpened.

Another object of the present invention is to provide a pencil sharpener having means to prevent continued cutting away of the pencil after it has been sharpened to a predetermined degree.

provide a pencil sharpener having a readily replaceable'blade and blade holder.

Another object of the present invention is to provide a pencil sharpener having means to hold a pencil being sharpened against rotation.

Anotherobject of the present invention is to provide a portable pencil sharpener that can 30 1. in and out of the mechanism.

Fig. 4 is a perspective view of the blade-and blade holder; and

Fig. 5 is a perspective view of the cam.

The present invention comprises 'a pencil sharpener adapted to rest on a desk, table, drawing board, etc., and be operated to sharpen a pencil by inserting the pencil in an opening in the top thereof and into contact with a cutting blade carried by a cam. Downward pressure of the pencil against the blade and the cam move said blade and cam longitudinally of the pencil sharpener to cause the cam surfaces of said cam to move across a stationary cam actuating pin. Movement of the cam surfaces across the pin causes the cam and blade to rotate relativeto the pencil to thereby cause said blade to sharpen the pencil. When the downward stroke of the pencil and cam is completed release of the pressure of the pencil against the blade permits a spring'to move the cam and blade upwardly to bring a second cam surface into contact with Anotherobject of the present invention is to beconveniently operated while setting on a desk,

drawing board, table or the like.

Other objectsv of the invention will be obvious and will in part appear hereinafter.

The invention accordingly comprises the product possessing the features, properties and the relation of components which are exemplified in the following detailed disclosure, and the scope.

of the application of which will be indicated in the claims. I

, For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawing wherein:

Figure 1 is an elevational view, partly in section, showing the pencil sharpener of the present invention with cam half way depressed;

Fig. 2 is a sectional view taken on line II-II 'of Fig. 1 and looking in the direction of the aring the cam andblade hplder insection;

the stationary cam actuating pin to'continue to rotate the cam and blade in the same direction whereby the pencil is also sharpened during its outward stroke.

The blade and cam are contained in a housing member having a pencil receiving opening in alignment with said blade and cam. The pencil receiving opening is preferably so shaped that it holds the pencil against rotation as it is moved The blade is held by a blade holder which is carried by the operating cam is such a manner that it is readily removable therefrom to permit the insertion of a new blade and blade holder when the blade in use becomes dull.

Referring now to the drawing there is disolosed a tWo part housing member I 0 comprising a bottom part l2 and a top part l4, adapted'to be removably connected together, as by threads it. Top part I4 is comprised of a circular top piece [8 which is provided with concentric depending outer and inner cylindrical sleeves or flanges 20 and 22 respectively. Flanges 20 and 22 cooperate to form an annular slot or groove 24, which houses a cam operating spring and sleeve in a manner to be explained hereinafter, and flange 22 also defines a vertical axial bore 26. A hexagonal hole 28 extends through the center of top piece I8 and is of such a size as to permit a pencil having a hexagonal cross-section to pass therethrough into the housing I0 but which holds such a pencil extending therethrough against rotation.

' A cylindrical barrel cam 30 having an axial bore 31 and a continuous cam slot 32 formedin its periphery is journaled for both reciprocation and rotation in the axial bore 26 formed by inner flange 22. An inwardly projecting cam actuating pin 34 is carried by inner flange 22 adjacent its lower edge and extends into bore 26 and into cam slot 32. Cam slot 32 is defined by two side walls 36 and 38 each of which form a cam surface on oppositehalvesof the cam barrel, i. e, wall 36 forms acam surface on the right hand side of barrel cam 30 as viewed in Fig. 1, and wall 38 forms a cam surface on the left side. The cam surface formed by side wall 38 is engaged by pin 34 as the cam barrel moves downwardly in bore 26 to rotate said barrel in a counterclockwise dig. rection as viewed in Fig. 2. The cam surface formed by side wall 35 is engaged1bypin: as the cam barrel moves upwardly to continue to rotate said barrel in a counterclockwise direction. The apexes 36a and 3% formed by the changes in direction of'side wall 36 are radially displaced from the apexes 38a and 38b formed by the changes indirection of side wall 38 so that the start :of the. cam surface formed by side wall 36 is -beneath apex 35a and thestart of the cam surface formed by side wall 38- is above apex 36b. Thus-it will be seen that as barrel earn 3 is moved downwardly in bore 25 the cam surface formedby side wall 38..is.broueht into engagement with cam actuating pin 34 to rotate said barrel cam .u-nti-l saidoin is contacted by the apex 38w adj acent the: upper edge I of the: barrel. It will be: noted that when a ex-38a is-contacted by: pin-341 that pin 34' isbeyond apex 35a formed by 'sidewall'fli'andis above the beginning of the camsurfacgformed by wall 36; Therefore; when barrel cam 30' moves upwardly pin 34 contacts the camsurface portion of sidewall36 and that cam surfacecontinues to rotate barrel cam 30 in a counterclockwise direction as said cam moves upwardly. When barrel cam 3!) reaches its uppermostposition apex 36b formed by side wall 36* adjacent to the lower edge of said barrel cam is: contacted bypin 34 to prevent any further upward movement of the cam. It-will be noted that'apex 35b is beyondapex-38b so that downward movement of barrel cam 39 causes pin 34 to engage the cam surface portion of side wall 38- to cause the cam surface formed thereby to start or contin-ue, as the case may be, the counterclockwise rotation of said cam.

Means are provided for retaining barrel cam 3min bore 26 and for permitting it to move down wardly-i-n saidbore under the thrust of apencil being sharpened; and to'return it to its uppermost position when said thrust is removed whereby cam slot32and-pin 34 cause it-to rotate. The retainingmeans comprises a sleeve 49 slidingly embracing the outer surface of flange 22- and having'a-n outwardly turned annular-flange 42 formed on its upper-end, and an inwardly turned flange 4'4 formed on its lower end. Inwardly turned flange: 44: is of sufficient width to extend beneath flange 22and engage the bottom edge of barrel cam 30. to-suppcrt said cam for rotation thereon. A" heli'cal spring llfi i housed in annular slot 24 so. as to engage the under surface of outwardly turned flange 42 to support said flange and through it sleeve tn and'barrel cam 30. Spring 46 'issupported in annular slot or groove 24 by means of a snap or clamping ring' lBwhich engages in an annular groove 50 formed in the inner surface of flange 20. It will therefor be seen that barrel earn 30' is supported in housing lfi by-meansof helical'spring 46 acting through sleeve 40.

A generally cylindrical blade holder 52 is removably carried in the bore of barrel cam 30, to move said cam downwardly under the thrust of a pencil and for rotation by said cam, by means of a spring clip 54. Spring clip 54 has a bent over upper end 56 which is located in a notch 58 formed in the upper edge of barrel cam 30 and is attached thereto by means of a pin or rivet 60. Spring clip 54' extends downwardly. within the bore oi'barrel cam 36 to adjacent the lower edge of said barrel cam at which point it terminates in an inwardly bent over lower end 51 adapted to engage the under side of blade holder 52. Blade holder 52 is provided with a tapered axial openingor hole 62, the taper of which corresponds to the taper it is desired to impart to the pencils to be sharpened by the pencil sharpener of therpresent invention. A spiraling slot 64, generaly V shaped in cross section, extends from theupperedge of said blade holder to, itslower edge n llfifi f l is u s an ally radia to blade holder52 and its other wall H3 is at sub! stantially degrees to wall 66. A knife or blade 5.8-. is fixedly mounted by any convenient means as, for example, rivets 12. to the Wall 10 of slot 64. Blade 68 is so located on wall 10 of blade holder 52 that its cutting edge 14 projects into the tapered opening 01' hole 64 through the spiral slot 64 a slight distance so thatwhen said blade and blade holder are rotated relative tea pencil located in opening 62 said bladew-ill shave the wood andlead of said pencil to formanew writing point thereon. It will benoted, that. due to the spiraling of slot 64 knife or blade 68spira1s down blade holder 52 so that its cutting edge is at an angle to the longitudinal axis of a. pencil placed in said blade holder wherebysaidknife cuts across the grain of; the wood to thereby cuts noothly and easily. The periphery of blade holder 521s provided with a longitudinal notch [6 which. exen s h qu h u t l n on itudinal notch 16 forms a passageway forreceiving spring clip 54 to permit said clip to extend from adjacent the upper surface of barrel cam 39 to adjacentits lower edge to position its inwardly bentover end 517 beneath said blade holder. Notch .16 also func: tions as a keyway which cooperates with spring clip 5 4, which also functions asa key, to prevent relative rotation between blade holder 52and cam 30 so that rotation of said cam will also rotate said blade holder. It will be seen that spring clip 54 releasably holds blade holder 52 in thebore e am 9 and tha sai ade hol an readily be removed-from said cam by swinging inwardly bent over endlfl of said clip radially outwardly from under said blade holder whereupon it will drop out of said cam. If blade 68 has become dull from prolonged use a new blade holder and sharp blade can be inserted incam 30 by again swinging bent over end 51 outwardly unti-lit can pass'into notch 16 and then sliding the blade holder upwardly in bore 3| of cam 30 until said bent ever end emerges from the lower end of notch 16 and snaps under said blade holder.

A pencil lead engaging projection 18 is formed on thelower surface of blade holder 52 in such a manner that a portion of its upper surface projects beneath the axis of downwardly tapering opening or hole 62. The upper surface of pencil lead engaging projection 18 is located slightly above what would be the apex of tapering opening or hole 52 so that the lead of a pencil being sharpened engages said projection before it has been out completely across and thereby prevents continued cutting away of the pencil after a predetermined point has been formed on the pencil.

The mode of operation of the present invention is as follows. The pencil sharpener is placed in an upright position on a table or drawing board and a pencil havin a hexagonal cross-section is inserted in hexagonal hole 28 in top piece l8 until its end engages in the downwardly tapering hole 62 in blade holder 52. Continued downward movement of the pencil forces blade holder 52 downwardly and this downward movement of said blade holder by reason of spring clip 54 is transmitted to and moves barrel cam 30 downwardly to bring its cam surface 38 into engagement with cam actuating pin 34 whereby said pin causes said barrel cam 30'to rotate in a counterclockwise direction as viewed in Fig, 2. counterclockwise rotation of barrel cam 30 is transmitted to bladeholder 52 by spring clip 54 and causes knife or blade 68 carried by blade holder 52 to shave off wood and lead from the end of the pencil. When the end of the downward stroke is reached, i.'e. when apex 38a in cam surface 38 engages cam actuating pin 34, downward pressure on the pencil being sharpened is relaxed a suificient amount to permit helical spring 46 to lift barrel cam 30 and blade holder 52 whereby pin 34 engages cam surface 36 to continue the counterclockwise rotation of said cam and blade holder, and continue shavin wood and lead, during the upward movement of said cam and blade holder. When the pencil has been sharpened to a predetermined desired extent the end of the pencil lead will engage projection 18 and said projection will prevent the pencil from entering tapering hole 62 thereafter and will thus hold the pencil from continuing to engage blade 68 whereupon any further reciprocation of cam 30, blade holder 52 and blade 68 will not cut the pencil.

Shaving and chips removed from the pencil during the sharpening operation fall into the bottom part l2 of housing It through the spiral slot 64 and are removed therefrom from time to time as may be convenient.

Since certain changes may be made in the above product without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. In a pencil sharpener the combination comprising a housin having an outer wall and an inner cylindrical sleeve spaced therefrom, a cylindrical barrel cam having an axial bore therethrough carried by said sleeve for reciprocation and rotation therein, said cam having a cam slot formed in its periphery defining two cam surfaces, an abutment projecting from the inner wall of said sleeve and engaged in said cam slot, a blade removably mounted in the bore of said cam and adapted to be engaged by the end of a pencil to be sharpened, said blade and said cam being adapted to be moved in one direction by pressure from a pencil in engagement with said blade to cause one of said cam surfaces to engage and move across said abutment to rotate said cam and blade, a spring in the space between said wall and said sleeve, and mean connecting said spring to said cam, said sprin being capable of moving said cam and blade in the other direction upon release of pressure from said pencil to cause the second cam surface to engage and move across said abutment to thereby continue to rotate said cam and blade in the same direction.

2. In a pencil sharpener the combination comprising a housing having an outer wall and an inner cylindrical sleeve spaced therefrom, a'cylindrical barrel cam having an axial bore therethrough carried by said sleeve for reciprocation and rotation therein, said cam having a cam slot formed in its periphery defining two cam surfaces, an abutment projecting from the inner wall of said sleeve and engaged in said cam slot, a blade removably mounted in the bore of said cam and adapted to be engaged by the end of a pencil to be sharpened, a second sleeve surrounding said inner sleeve, said second sleeve having an inwardly turned flange on one end and an outwardly turned flange on its other end, said inwardly turned flange engaging one end of said cam, a compression spring between said second sleeve and said wall and having one of its ends in engagement with said outwardly turned flange and its other end in engagement with retaining means carried by said wall, said blade and cam being adapted to be moved in one direction by pressure from a pencil in engagement with said blade to compress said spring and to cause one of said cam surfaces to engage and move across said abutment to rotate said cam and blade, said spring acting through said second sleeve being capable of moving said cam and blade in the other direction upon release of pressure from said pencil to cause the second cam surface to engage and move across said abutment to thereby continue to rotate said cam and blade in the same direction.

3. In a pencil sharpener the combination comprising a housing having an outer wall and an inner cylindrical sleeve spaced therefrom, a cylindrical barrel cam having an axial 'bore therethrough carried by said sleeve for reciprocation and rotation therein, said cam having a cam slot formed in its periphery defining two cam surfaces inclined in opposite directions and having the start of each cam surface overlapped by the finish of the other, an abutment projecting from the inner wall of said sleeve and engaged in said cam slot, a blade removably mounted in the bore of said cam and adapted to be engaged by the end. of a pencil to be sharpened, a second sleeve surrounding said inner sleeve, said second sleeve having an inwardly turned flange on one end and an outwardly turned flange on its other end, said inwardly turned flange engaging one end of said cam, a compression spring between said second sleeve and said wall and having one of its ends in engagement with said outwardly turned flange and its other end in engagement with retaining means carried by said wall, said blade and cam being adapted to be moved in one direction by pressure from a pencil in engagement with said blade to compress said spring and to cause one of said said cam surfaces to engage and move across said abutment to rotate said cam and blade, said spring acting through said second sleeve being capable of moving said cam and blade in the other direction upon release of pressure from said pencil to cause the second cam surface to engage and move across said abutment to thereby continue to rotate said cam and blade in the same direction.

4. In a pencil sharpener the combination comprising a housing including a top having an outer depending wall and an inner depending cylindrical sleeve spaced from said wall, said top having a hexagonal hole for admitting a pencil into said housing and holding it against rotation, a cylindrical barrel cam having an axial bore therethrough carried by said sleeve for reciprocation and :rotation a therein; said oam; having a cam slot formed in its periphery: defining two cam surfaces, an abutment projecting from the inner wall of said sleeve and engagedin said cam slot, a blade removably mounted in the bore of said cam inalignment with said hole and adapted to be engaged by the end of a pencil inserted there.- through, said blade and said cam being adapted to be moved-in one direction by pressure from a pencil in engagement with said blade to cause one of said cam surfaces to engage and move across said abutment to rotate said cam and blade, a spring in the space between said wall and said sleeve, and means connecting said spring tosaid cam, saidspring being capable of moving; said. camand bladein the other direction upon release of pressure from said pencil to cause the second cam surface to engage and move across said abutment to thereby continue to rotate said'cam and blade in the same direction.

5. Ina pencil sharpener the combination-comprising a housing having an outer Wall and an inner cylindrical sleeve spaced therefrom, a cylindrical barrel cam having an axial bore therethrough carried by said sleeve-for reciprocation and rotation therein, said cam having a cam slot formed in its periphery defining two cam surfaces, an abutment projecting from the inner wall of said. sleeve and engaged in said cam slot, a blade holder removably mounted in the bore of said-cam and held against movement relative thereto, said blade holder being provided with a tapered axial hole extending t'herethrough, a blade carried by said blade holder, said blade,

blade holder and cam being adapted to be moved in one direction by pressure from a pencil in engagement with said bladenand'b'lade holder to cause one 'of said cam surfaces to engage and move across said abutment to rotate them, a spring in the space between said Wall and said sleeve, means connecting said spring to said cam, said spring being capable of moving said cam and blade in the other direction upon release of pressure from said pencil to cause the second cam surface to engage and move across said abutment to thereby continue to rotate said cam, blade holder and blade in the same direction, and a stop member carried by said blade holder and extending across the small end of said tapered hole for engagementby the lead of said pencil whena. predetermineddegree of sharpness. has been attained to prevent further cutting away ofjthe pencil.

ROBERT. C. GWIN, J R.

REFERENCES CITED The following references are of record in the file of this patent:

UNITEDSTATES PATENTS Number Name Date 819,123 Clough May 1, 1906 1,201,458 Haley Oct. 17, 1916 1,204,604 Spengler Nov. 14, 1916 1,529,687 Bowen Mar. 17, 1925 FOREIGN PATENTS Number Country Date 262,576 Switzerland -1 July 15, 1949 

